Flight UA971 was on its way to Chicago’s O’Hare International Airport from Rome Saturday when the flight had to make an unscheduled diversion due to an unruly passenger aboard. (Published Sunday, June 21, 2015)

The airline company, in an email to the passengers, offered an electronic travel certificate of up to $200. The voucher is only valid toward the purchase of one electronic airline ticket on United and expires in one year.

Ellisa Slonim said she and her fiance were on their way home after just getting engaged when their flight was diverted and their travel delayed for several hours. Slonim and nearly 300 other Chicago-bound passengers were forced to spend the night on the floor of an airport terminal in Belfast, Northern Ireland.

She and seven of her family members on the flight said they each received an email with the voucher.

It was not clear how many of the passengers received the voucher, but United Airlines told NBC Chicago all passengers would get a refund and a $200 travel voucher.

Slonim said she paid $900 each way for her trip.

Flight UA971 was on its way to Chicago’s O’Hare International Airport from Rome Saturday when the flight had to make an unscheduled diversion due to an unruly passenger aboard. Law enforcement met the crew at a terminal in Belfast to take the disruptive passenger into custody. The Boeing 777 landed at 6.59 p.m. local time.

“Then they left all the passengers, including my husband, on the tarmac in the plane for 5 hours before removing them and telling them to take their pillows and blankets because they will have to sleep on the floor in the Belfast airport,” Jacquelyn George wrote in an email to NBC Chicago.

A spokesperson for United Airlines could not confirm how many hours the passengers sat on the tarmac during the diversion, but asserted that by the time the incident was resolved the crew had reached FAA’s maximum work hour limits, so the plane was not able to travel on.

With not enough local hotel rooms available with room for the 269 passengers, they were asked to pass the time in the terminal.

Customers were accommodated with food and “other services” to make them comfortable for the overnight stay, according to the airline’s spokesperson.

Chicago passenger Billy Saviano told NBC News the flight was finally supposed to leave the airport Sunday at 1 p.m. local time but it was delayed until 4 p.m. — 21 hours after they landed in the U.K. and some 24 hours after they originally left Italy.

Saviano also expressed frustration in having to sit on the tarmac for a total of five hours before they were allowed inside. Then, he says, they were left in the dark once again.